Table II.
Sex, gestation, parity and maternal age distributions in the 20 studies
| Study | Sex N (%) male |
Gestation Median (IQR) days |
Parity N (%) first born |
Maternal age Median (IQR) years |
|---|---|---|---|---|
| Southampton 1, UK | 296(53.1) | 282(275, 288) | 293(52.6) | 26(23, 30) |
| Southampton 2, UK | 263(50.5) | 282(275, 287) | 249(47.8) | 28(24, 31) |
| Southampton 3, UK | 190(50.4) | 281(275, 286) | 180(47.8) | 27(23, 30) |
| Southampton 4, UK | 46(45.1) | 279(273, 287) | 56(54.9) | 28(24, 32) |
| Preston, UK | 503(49.6) | 282(275, 288) | 824(82.3) | 25(22, 29) |
| Sheffield, UK | 2284(51.7) | 281(275, 288) | 1701(39.1) | 27(23, 32) |
| Farnborough, UK | 879(52.4) | 284(277, 284) | 778(46.7) | 28(25, 30) |
| Isle of Man, UK | 192(49.5) | 284(278, 290) | 338(100.0) | 26(22, 29) |
| Aberdeen, UK | 113(48.5) | 281(274, 287) | 233(100.0) | 23(21, 25) |
| Helsinki, Finland | 3051(50.9) | 279(273, 286) | 2567(42.9) | 27(23, 31) |
| Mysore 1, India | 651(52.6) | 279(272, 283) | 472(38.2) | 23(20, 26) |
| Mysore 2, India | 291(48.7) | 276(270, 281) | 300(50.3) | 24(20, 26) |
| Pune 1, rural India | 340(53.7) | 275(270, 282) | 195(30.8) | 21(19, 23) |
| Pune 2, India | 136(50.6) | 276(270, 283) | 48(18.1) | 25(22, 28) |
| Kandy, Sri Lanka | 232(51.0) | 284(284, 286) | 218(47.9) | 27(23, 31) |
| Beijing, China | 1180(48.5) | 281(274, 287) | 1165(47.9) | 27(24, 32) |
| Kasaji, rural DR Congo | 177(52.4) | 277(271, 283) | 95(28.1) | 23(19, 29) |
| Imesi rural Nigeria | 120(44.6) | 9(3.8) | 25(20, 30) | |
| Kingston 1, Jamaica | 218(44.5) | 278(271, 284) | 239(48.9) | 26(23, 30) |
| Kingston 2, Jamaica | 36(51.4) | 279(271, 284) | 39(55.7) | 26(20, 31) |